Effect of the morphology of films of polyaniline derivatives poly-2-[(2E)-1‑methyl-2‑butene-1‑yl]aniline and poly-2-(cyclohex-2‑en-1‑yl)aniline on sensory sensitivity to humidity and ammonia vapors

The influence of the morphology of polyaniline derivatives on the electrical conductivity, sensory sensitivity to air humidity of thin-film structures based on them, and the reaction to ammonia vapors has been investigated. Aniline derivatives, as well as polymers based on them, poly-2-[(2E)-1‑methyl-2‑butene-1‑yl]aniline and poly-2-(cyclohex-2‑en-1‑yl), were synthesized. Using a scanning electron microscope, the morphology of the surface of thin films obtained from a solution of synthesized polymers by centrifugation on sitall substrates was studied. Studying the nature of morphology is extremely important when creating sensory devices. On the basis of these polymers, samples of resistive thin-film structures were prepared, the dependence of their electrical conductivity on the relative humidity of the air and the dependence of the current passing through the sample with a change in the concentration of ammonia vapors were measured. The influence of the morphology of the surface of the films on the sensitivity of sensors to air humidity has been experimentally revealed and the prospects of using the studied films in humidity sensors have been shown. According to the experimental data, it can be seen that poly-2-[(2E)-1‑methyl-2‑butene-1‑yl] aniline film has the highest conductivity at the same values of relative humidity.

1. Ministry of Education and Science of the Russian Federation - This work was supported by the State assignment for the implementation of scientific research by laboratories (order MN-8/1356 of 09/20/2021).